WHICH ARTERIES SUPPLY THE HEAD AND NECK

AND WHAT ARE THEIR ORIGINS

Common carotid Internal carotid

Subclavian Vertebral-Basilar

On the right side from the Brachiocephalic trunk

On the left side direct from the aortic arch

HOW DOES THE VERTEBRAL ARTERY ENTER

THE CRANIAL CAVITY

The vertebral artery is the FIRST branch of the subclavian

It branches between the subclavian outlet and the interscalene triangle

Ascends through the transverse foramina starting at C6

Passes along superior surface of posterior arch of C1

Enters through the foramen magnum

DESCRIBE THE DRAINAGE OF THE CRANIAL

CAVITY

The dural venous sinuses empty into the Internal jugular veins

Dural venous sinuses are the endothelial- lined channels between the layers

of the dura mater

NO VALVES OR SMOOTH MUSCLE

Extracranial veins empty into internal jugular vein or subclavian

The internal jugular and subclavian brachiocephalic superior vena cava

Intra and extra-cranial veins communicate via EMISSARY VEINS

IMPORTANT ROUTE OF INFECTIONS

DESCRIBE THE LOCATION OF THE DEEP

CERVICAL CHAIN

The deep cervical chain consists of 15-30 nodes that lie along the carotid

sheath, deep to the sternocleidomastoid muscle.

Deep cervical nodes are subdivided into two groups based upon their location

relative to the superior belly of the omohyoid muscle: Superior and Inferior

IN WHAT LOBE DOES THE LATERAL (SYLVIAN)

FISSURE TERMINATE?

The Parietal Lobe

THE CAUDAL BORDER OF THE PARIETAL LOBE IS

BEST SEEN IN WHAT VIEW

Medial : the parieto-occipital sulcus is apparent in this view.

NAME FOUR FUNCTIONS OF THE TEMPORAL LOBE

Speech

Memory

Olfaction

Audition

NAME THE TWO BLOOD SUPPLIES OF THE BRAIN

Vertebral-Basilar

Temporal

Occipital

Brain stem

Cerebellum

Internal Carotid

Diencephalon

Frontal

Parietal

Basal Ganglia

Internal Capsule

VERY LITTLE MIXING

LAYERS OF HEAD/NECK

Skin

Connective tissue (Dense) – External blood vessels are here

Aponeurosis of the epicranium

Loose connective tissue

Pericranium – Diploe

Emissary veins

Periosteal Dura mater

Meningeal Dura mater – meningeal arteries, dural venous sinuses

Bridging veins, Arachnoid granulations

Arachnoid mater

Subarachnoid Space – Cerebral/cerebellar arteries/veins

Pia Mater

Brain

NAME TWO KEY SYMPTOMS OF A BLOCKAGE OF THE

VERTEBRAL-BASILAR CIRCULATION

Vision problems (occipital)

Dizziness (cerebellum)

NAME THE BRANCHES OF THE VERTEBRAL

ARTERIES

PICA

Anterior Spinal

Posterior Spinal

Basilar

PICA

PICA runs circumferentially around the medulla

Gives off penetrating branches that supply the dorsolateral medulla and the

choroid plexus of the fourth ventricle.

PICA then continues superiorly to supply posterior and inferior parts of the

cerebellum and cerebellar peduncles.

ANTERIOR SPINAL

Supplies median and paramedian aspects of the medulla oblongata and

anterior 2/3 of spinal cord

NAME THE BRANCHES OF THE BASILAR ARTERY

AICA

Pontine

Superior Cerebellar

Posterior Cerebral Artery

AICA

Travels along the caudal end of the middle cerebellar peduncle

Supplies the upper medulla and lower pons, and the anterior inferior surface of

the cerebellum.

SUPERIOR CEREBELLAR

Travels along the pons and middle cerebellar peduncle

Supplies the superior cerebellum

POSTERIOR CEREBRAL ARTERIES

The basilar artery branches at the level of the midbrain and each posterior

cerebral artery supplies:

MEDIAL and INFERIOR surface of the temporal and occipital lobes,

Thalamus

Internal structures

Hippocampus*

Occlusion of PCA may lead to visual field deficits. Patients may be unable to

drive or read, resulting in major limitations in their quality of life, despite normal

motor function.

Thalamic involvement can produce sensory loss or thalamic pain syndrome, a

hypersensitivity to pain.

NAME THE BRANCHES OF THE INTERNAL

CAROTID SYSTEM

Opthalmic artery

Middle cerebral artery

Anterior cerebral artery

Anterior choroidal artery

Lenticulostriate arteries

OPTHALMIC

Supplies orbit, eye and scalp

Shade going down over one eye

RISK OF FUTURE STROKE

MIDDLE CEREBRAL ARTERIES

Runs laterally between the temporal lobe and the frontal lobe to emerge from

the LATERAL sulcus (sylvian fissure).

Each MCA divides into several branches to supply the LATERAL surface of the

hemisphere, including the primary motor and primary sensory areas of cortex,

located in the pre-central and post-central gyri.

ANTERIOR CEREBRAL ARTERIES

Runs along the medial surface of each cerebral hemisphere and curves

dorsally and caudally to lie superior to the corpus callosum – wraps around

corpus callosum

The ACAs supply the MEDIAL portions of the frontal and parietal lobes as well

as the corpus callosum.

Distal branches of the ACAs supply the MEDIAL surface of the parietal lobe,

including the paracentral lobule.

LENTICULOSTRIATE ARTERIES

Small arteries arising from the middle and anterior cerebral arteries that

penetrate the brain in the anterior perforated substance

Supply deep structures: basal ganglia

ANTERIOR CHOROIDAL ARTERIES

Branch off INTERNAL CAROTID

Supplies the optic tracts and the posterior limb of the internal capsule.

OPTIC CHIASM

The point of intersection between the optic nerve CN II and the optic tracts

WHAT LIES BETWEEN THE TWO CEREBRAL

PEDUNCLES?

Interpeduncular fossa: exit of oculomotor nerve

Mamillary bodies

DAMAGE TO THE FRONTAL LOBE IMPAIRS…

the ability to make decisions, including anticipating the future consequences of

an action and responding appropriately in social situations.

THE CINGULATE GYRUS IS INVOLVED IN…

The cingulate gyrus is a prominent part of the limbic system, which plays a role

in emotion, behavior, long-term memory and olfaction.

THE INTRAPARIETAL SULCUS DIVIDES THESE

TWO STRUCTURES

Superior and Inferior Parietal Lobules

A PATIENT WHO HAS DIFFICULTY RECOGNIZING

ONE SIDE OF THEIR BODY MAY HAVE DAMAGE

TO THIS REGION

Inferior parietal lobule

THE PRECENTRAL AND POSTCENTRAL GYRI

COME TOGETHER TO FORM THE…

Paracentral lobule

IN THE OCCIPATAL LOBE, THE _____ FISSURE

DIVIDES THE ______ AND _______

Calcarine

Cuneus : upper retina – lower visual field

Lingual gyrus: lower retina – upper visual field

THE CAUDAL PORTION OF THE SUPERIOR

TEMPORAL GYRUS HAS SMALL OBLIQUE GYRI

Transverse temporal gyri (of Heschl)

Primary auditory cortex

THESE GYRI CAN BE VIEWED ON THE INFERIOR

SURFACE OF THE BRAIN

Parahippocampal gyrus (medial)

Uncus

Occipito-temporal

THE INSULAR CORTEX IS INVOLVED IN…

Taste

Visceral physiological function

Nicotine addiction

NAME THE FOUR PARTS OF THE CORPUS

CALLOSUM FROM ROSTRAL TO CAUDAL

Rostrum

Genu

Body

Splenium

NAME THE 5 COMMISSURES

Corpus callosum

Anterior commissure

Posterior commissure

Fornix

Optic chiasm

WHAT IS THE RELATION OF THE

HYPOTHALAMUS TO THE THALAMUS

The hypothalamus is the rostral and inferior border of the thalami.

The hypothalamus is a smaller brain structure that comprises the inferolateral

borders of the third ventricle.

The third ventricle forms the medial border of the hypothalamus.

The anterior border of the hypothalamus is the lamina terminalis, a thin sheet

of neural tissue that marks the rostral boundary of the original neural tube

from which the brain and spinal cord developed.

The optic chiasm (mentioned above) is the rostral border of the

hypothalamus.

The mammillary bodies form the caudal border of the hypothalamus

The hypothalamus also includes the infundibulum, which is the pituitary stalk

connecting the pituitary to the hypothalamus. The hypothalamus has

homeostatic and reproductive functions.

NAME THE IMPORTANT CISTERNS IN THE

CRANIAL CAVITY

Cerebellomedullary cistern

Superior cistern

Interpeduncular cistern

Pontine cistern

Chiasmatic cistern

Cistern of lateral fossa

Lumbar cistern

THE CSF ESCAPES TO THE SUBARACHNOID

SPACE THROUGH…

Lateral foramina of Luschka

Midline median aperture of Magendie

NAME THE THIN MEMBRANE THAT SEPARATES

THE LATERAL VENTRICLES

Septum Pallucidum

WHAT IS THE RESULT OF A BUILDUP OF CSF

Hydrocephalus

EACH VENTRICLE IS ASSOCIATED WITH A

PRINCIPLE BRAIN REGION..

Lateral ventricle – telencephalon

Third Ventricle – diencephalon

Cerebral aqueduct – midbrain

Fourth ventricle – medulla and pons

WHAT NERVE EXITS THE BRAIN AT THE SULCUS

THAT DIVIDES THE OLIVES FROM THE

MEDULLARY PYRAMIDS

Hypoglossal nerve

THE SUPERIOR COLLICULI ARE INVOLVED IN…

Coordinating eye movements – SEEING

Inferior - auditory

A THIN SHEET OF NEURAL TISSUE THAT MARKS

THE ROSTRAL BOUNDARY OF THE ORIGINAL

NEURAL TUBE FROM WHICH THE BRAIN AND

SPINAL CORD DEVELOPED

Lamina Terminalis – anterior border of hypothalamus

DESCRIBE THE FUNCTION OF CRANIAL

FONTANELLES DURING PARTURITION.

The softness of the cranial bones of the neonate and their loose connections at

sutures enable the skull to change shape (mold) as it passes through the birth

canal.

IDENTIFY THE CLINICAL SIGNIFICANCE OF THE

ANTERIOR FONTANELLE IN NEONATES.

Palpation of the fontanelles is a part of the physical examination of an infant

A bulging or tense fontanelle indicates raised intracranial pressure

A sunken fontanelle indicates dehydration

Cerebral arteries cause pulsation and blood samples can be obtained here

IDENTIFY THE BONE IN THE SKULL THAT

HOUSES THE CAROTID CANAL

Petrous Temporal Bone

Also inner and middle ear and facial canal

Structures of the inner ear = cochlea, semicircular canals

Structures of middle ear = Auditory Ossicles = malleus, incus, and stapes

The internal carotid artery exits the petrous bone, enters the cavernous

sinus, does a big wiggle and then branches into the ACA and MCA

LIST THE FOUR BONES INVADED BY

PARANASAL AIR SINUSES DURING BIRTH

Frontal

Ethmoid

Sphenoid

Maxillary

IDENTIFY THE BONES OF THE SKULL

ethmoid

frontal

mandible

maxillary

occipital

nasal

palatine

parietal

sphenoid

temporal

vomer

zygomatic

Note: the two frontal bones

fuse (usually) by 6 years of age.

Until then they are separated by

the metopic suture.

THE SKULL

The neurocranium is further divided

into the cranial base (basicranium)

and the calvaria. The calvaria

consists of the flat bones that form

the walls and roof of the

neurocranium.

Viscerocranium: frontal, maxilla,

nasal, zygomatic, palatine,

mandible

WHAT IS THE CAUSE OF CRANIOSYNOSTOSIS?

Premature fusion of sutures

WHAT ARE THE COMPONENTS OF THE NASAL

SEPTUM

Vomer

Perpendicular plate

of ethmoid

Nasal septum

cartilage

NAME TWO IMPORTANT GROWTH CARTILAGES

OF THE SKULL

Spheno-occipital synchondrosis

Nasal septum cartilage

Can be affected by achondroplasia!

Pterion

(“P” is silent)

Styloid process

Mastoid process

Ramus of mandible

Angle of mandibleBody of mandible

THE INTERNAL CAROTID ARTERY PASSES OVER

WHICH FORAMEN BEFORING ENTERING

CANAL?

Foramen lacerum

MIDDLE EAR IS LOCATED LATERAL OR MEDIAL

TO THE SEMICIRCULAR CANALS?

Lateral

THE FACIAL NERVE EXITS THE SKULL THROUGH

THE ________?

Stylomastoid foramen

LIST THE THREE DIVISIONS OF CN V

(TRIGEMINAL) AND IDENTIFY THE NERVE

COMPONENTS CARRIED BY EACH.

V1 - Opthalmic

sensory only

V2 - Maxillary

sensory only

V3 - Mandibular

sensory + motor root

innervations muscles of

mastication and some

other smaller ones

LIST THE THREE PRIMARY BRANCHES OF CN VII

(FACIAL) AND DESCRIBE THEIR FUNCTIONS.

“Motor”

Motor to muscles of facial expression; motor to stapedius muscle of middle

ear

Greater petrosal

Delivers preganglionic parasympathetic fibers to pterygopalatine ganglion

Chorda tympani

Delivers preganglionic parasympathetic fibers to submandibular ganglion;

taste sensation from anterior 2/3 of tongue

IDENTIFY THE SENSORY AND AUTONOMIC

FUNCTIONS OF CN IX (GLOSSOPHARYNGEAL).

Somatic Sensory from posterior 1/3 of tongue, nasopharynx, oropharynx,

tympanic cavity & internal surface of tympanic membrane, posterior soft palate

Taste sensation from posterior 1/3 of tongue

Visceral sensation from carotid body and carotid sinus

Autonomic preganglionic parasympathetic innervation to otic ganglion (parotid

gland)

IDENTIFY THE SENSORY, MOTOR AND

AUTONOMIC FUNCTIONS OF CN X (VAGUS).

Superior laryngeal nerve

Sensory from larynx superior to the vocal folds (internal branch); motor to cricothyroid and cricopharyngeus muscles (external branch)

Inferior (recurrent) laryngeal nerve

Sensory from vocal folds and inferior larynx

Motor to all intrinsic laryngeal muscles except cricothyroid

Additional branches

Sensory from dura, auricle, external auditory meatus, laryngopharynx

Visceral sensory from carotid body and carotid sinus, thoracic and abdominal viscera

Motor to pharynx, uvula and elevator of soft palate

Autonomic preganglionic parasympathetic innervation to terminal ganglia in walls of thoracic and abdominal viscera

LIST THE THREE CRANIAL NERVES THAT CARRY

SPECIAL SENSORY FIBERS AND IDENTIFY THE

MODALITY TO WHICH EACH IS DEDICATED.

CN I - Olfactory - Smell

CN II - Optic - Vision

CN VIII - Vestibulocochlear – Hearing and balance

LIST THE TWELVE CRANIAL NERVES AND

IDENTIFY THE FORAMINA OF THE CRANIAL

BASE THAT TRANSMIT THEM FROM THE

CRANIAL CAVITY. CN I – Olfactory - Cribriform plate of ethmoid bone to nasal cavity CN II – Optic - Optic canal of sphenoid bone to orbit CN III – Oculomotor - Superior orbital fissure to orbit CN IV – Trochlear - Superior orbital fissure to orbit CN V – Trigeminal

Opthalmic – Superior orbital fissure Maxillary – Foramen rotundum Mandibular – foramen ovale

CN VI – Abducens - Superior orbital fissure to orbit CN VII – Facial – Internal acoustic meatus and out stylomastoid foramen CN VIII – Vestibulocochlear – Internal acoustic meatus CN IX – Glossopharyngeal – Jugular foramen CN X – Vagus – Jugular foramen CN XI – Spinal Accessory – Enters foramen magnum, exits jugular foramen CN XII – Hypoglossal – Hypoglossal canal

IDENTIFY THE ARTERY OF ORIGIN OF THE

MIDDLE MENINGEAL ARTERY

External carotid artery → Maxillary artery → Middle meningeal artery

Middle meningeal through foramen spinosum

DISCUSS THE SIGNIFICANCE OF THE MIDDLE

MENINGEAL ARTERY WITH RESPECT TO

CALVARIAL FRACTURES AND EPIDURAL

(EXTRADURAL) HEMORRHAGE.

The middle meningeal artery lies under the thin pterion bone. A strong blow to

the side of the head can cause this bone to fracture. A fracture in the pterion is

called a calvarial fracture and commonly causes tears in the middle meningeal

arteries below. These tears lead to bleeding into the epidural space called

epidural (extradural) hemorrhage.

LIST THE NERVES THAT PROVIDE SENSORY

INNERVATION TO THE DURA AND DESCRIBE

THEIR GENERAL DISTRIBUTION.

Anterior fossa: trigeminal nerve – V1. V2. V3

Posterior fossa: C1-3 , Vagus and Hypoglossal nerves

Anterolateral – sphenoid

Posterolateral - mastoid

WHICH THREE CRANIAL NERVES ARE MIXED

NERVES?

Facial

Glossopharyngeal

Vagus

Also Trigeminal?

DISTINGUISH A DURAL VENOUS SINUS FROM A

PARANASAL SINUS.

Dural Venous Sinus

Between dural layers

Contains blood and CSF

Paranasal sinus

Between cranial bones around nose

Contains air

VENOUS DRAINAGE OF THE BRAIN…

Superior cerebral veins→ Superior sagittal sinus→ confluence of sinuses→ transverse sinus (usually right)→

becomes sigmoid sinuses → Internal jugular vein

Inferior sagittal sinus→ straight sinus→ confluence of sinuses→ transverse sinus (usually left) → becomes

sigmoid sinuses→ Internal jugular vein

Note the drainage is asymmetric in that the superior sagittal sinus drains into one of the transverse sinuses

and the straight sinus goes into the other.

Ophthalmic veins, middle cerebral veins, sphenoparietal sinus → cavernous sinus→

Superior petrosal sinus→ transverse sinuses→ becomes sigmoid sinuses→ Internal jugular vein

Inferior petrosal sinus→ Internal jugular vein

Note the cavernous sinus drains into both the superior and inferior petrosal sinuses (both of which eventually

end at the jugular vein)

DOES THE SUPERIOR SAGITTAL SINUS USUALLY

DRAIN INTO THE RIGHT OR LEFT TRANSVERSE?

Right

Straight Sinus goes to left

DISCUSS THE SIGNIFICANCE OF THE BASILAR

PLEXUS AND OCCIPITAL SINUSES IN THE

METASTASIS OF CANCER TO THE VERTEBRAE

AND BRAIN.

The occipital sinus, along with the basilar plexus (a.k.a transverse sinuses) of

veins located on the basioccipital clivus communicate with the internal vertebral

venous plexus through the foramen magnum.

Because these venous channels are valveless, compression of the thorax,

abdomen and pelvis (during coughing or heavy straining) may force venous

blood from these regions into the internal vertebral venous system and

subsequently into the dural venous sinuses.

As a result, pus in abscesses and tumor cells in these regions may spread to

the vertebrae and brain.

DEFINE “BRIDGING” VEINS. DISCUSS THE

SIGNIFICANCE OF BRIDGING VEINS TO DURAL

BORDER (SUBDURAL) HEMATOMAS.

“Cerebral and cerebellar veins - veins which drain brain tissue – drain to the

dural venous sinuses. These veins are often referred to as “bridging veins”

because they must “bridge” the subarachnoid space in order to gain access to

and open into the dural venous sinuses.

In light of this, extravasated blood from a torn bridging vein collects between

the dura and the arachnoid and results in a subdural (dural border) hemorrhage

LIST THE SEVEN (7) STRUCTURES CONTAINED

WITHIN THE CAVERNOUS SINUS OR ITS WALL.

Embedded

Oculomotor

Trochlear

Opthalmic CN V1

Maxillary CN V2

Pass through

Abducens

Internal Carotid

CSF IS RECYCLED INTO THE VENOUS SYSTEM

THROUGH THESE STRUCTURES

Arachnoid granulations superior sagittal sinus

DURAL VENOUS SINUSES LIE AT THE

SEPARATION OF THESE TWO STRUCTURES

The periosteal and meningeal dural layers

THE STRAIGHT SINUS IS FORMED BY THE …

Inferior sagittal sinus and the great cerebral vein (of Galen)

THE SICKLE-SHAPED FOLD OF DURA THAT

EXTENDS INTO THE LONGITUDINAL CEREBRAL

FISSURE OF THE BRAIN,

Cerebral Falx

Attachment: Crista Galli

TRANSVERSELY-ORIENTED FOLD OF DURA

WITHIN THE TRANSVERSE CEREBRAL FISSURE.

Cerebellar Tentorium

Attachment: Petrosal arch

LATERAL TO THE CEREBRAL FALX WHICH

ARTERY CAN BE IDENTIFIED WITHIN THE DURA?

Middle meningeal artery

THE SIGMOID SINUS BEGINS WHERE…

By definition the sigmoid sinus begins where the superior petrosal sinus joins

the transverse sinus

internal jugular vein begins where the inferior petrosal sinus joins the sigmoid

sinus

WHAT THREE STRUCTURES COMPOSE THE

SELLA TURCICA

Hypophyseal fossa

Anterior clinoid process

Dorsum sellae

HOUSES PITUITARY GLAND

THE OLFACTORY BULB SITS WITHIN THIS

STRUCTURE

Cribiform plate

AT WHAT LEVEL DOES THE CAROTID

BIFURCATIONS OCCUR?

C4

THE OPTHALMIC ARTERY TRAVELS WITH THE

________ AND IS A BRANCH OF THE _________

Optic nerve

Internal carotid artery

GIVEN HORIZONTAL, CORONAL OR

MIDSAGITTAL SECTIONS OF THE BRAIN,

IDENTIFY THE VASCULAR TERRITORIES OF MCA,

ACA, PCA, PICA, SCA, AICA, AND THE ANTERIOR

CHOROIDAL AND LENTICULOSTRIATE ARTERIES.

NAME THE ARTERIES THAT SUPPLY MEDIAL

BRAINSTEM STRUCTURES. NAME THE ARTERIES

THAT SUPPLY DORSOLATERAL BRAINSTEM

STRUCTURES.

Medial: Basilar, Anterior Spinal Artery

Dorsolateral: PICA, SCA, PCA

NAME THE BLOOD VESSELS THAT SUPPLY THE

SPINAL CORD.

The Spinal Cord is supplied by the vertebral

arteries and the anterior and posterior spinal

arteries.

Paramedian branches penetrate along the

ventro-medial fissure.

Circumferential branches penetrate white

matter on the lateral aspect of the cord to

supply ventral and lateral portions of the cord”

DEFINE A BERRY ANEURYSM. DISCUSS THE

SIGNIFICANCE OF BERRY ANEURYSMS IN

SUBARACHNOID HEMORRHAGE.

A berry or saccular aneurysm is an aneurism that arises in the small branching points of arteries near the circle of Willis

Abnormal widening due to weakness of vessel

Although a cerebral aneurysm may be present without symptoms, the most common initial symptom of a cerebral saccular aneurysm is a sudden headache from a subarachnoid hemorrhage (SAH).

85% in anterior circulation

DESCRIBE THE FUNCTIONS OF THE FOLLOWING

MUSCLES OF FACIAL EXPRESSION:

ORBICULARIS OCULI (ORBITAL AND PALPEBRAL

PARTS), ORBICULARIS ORIS, BUCCINATOR.

Orbicularis oculi - Blinking. Keeps your cornea and sclera wet by spreading

“lacrimal fluid” over it.

Palpebral part - involuntary, closes eye gently (blinking)

Orbital part - voluntary, more forceful as in photophobia

Orbicularis oris - seals lips and prevents drooling

Buccinator - keeps food out of the oral vestibule

IDENTIFY WHERE THE MOTOR PORTION OF CN

VII IS VULNERABLE TO INJURY.

The motor portion of CN VII is vulnerable to injury in neonatal skulls during

forceps delivery due to the absence of the mastoid and styloid processes.

Otherwise, they can be damaged from any superficial lacerations due to their

superficial location on the face. The facial nerve (motor portion) emerges from

the stylomastoid foramen and enters the parotid gland then branches.

Also, these facial nerves can be affected in cold weather.

DEFINE BELL (BELL’S) PALSY AND LIST ITS

COMMON SYMPTOMS. DESCRIBE HOW THE

MOTOR PORTION OF CN VII IS ASSESSED IN A

NEUROLOGICAL EXAM. Bell Palsy is defined as an idiopathic injury of the facial nerve affecting all or some of its branches.

Facial paralysis resulting from a dysfunction of CN VII. It is thought that inflammation of the facial nerve where it exits the facial canal causes pressure that impinges on that nerve, damaging the nerve and blocking conduction.

Herpes simplex-mediated viral inflammatory/immune mechanism is the most common cause of Bell’s Palsy, followed by Herpes zoster.

Symptoms include:

Sudden onset of unilateral facial paralysis

Sagging Eyebrows

Inability to close eyes

Disappearance of nasolabial fold

Mouth drawn on non-affected side

Neurological Exam of Motor portion CN VII include:

Testing Corneal Reflex (involuntary blinking in response of a foreign body touching the eye)

Ability to smile, squint and raise eyebrow

Sound Sensitivity

DISCUSS TRIGEMINAL NEURALGIA AND

IDENTIFY THE DIVISION OF CN V MOST OFTEN

AFFECTED.

Trigeminal neuralgia - intense nerve pain (“lightning-like”) that lasts for 15

minutes or more

There’s often a patch of skin called the “trigger zone” that is hypersensitive to

touch and precipitates the neuralgia

Maxillary nerve most often affected.

LIST THE FIVE LAYERS OF THE SCALP. IDENTIFY

THE LAYER IN WHICH THE ARTERIES AND VEINS

OF THE SCALP ARE LOCATED.

Skin

Connective tissue (Dense) - Blood vessels are here.

Aponeurosis of the epicranium

Loose connective tissue

Pericranium

LIST THE ARTERIES THAT SUPPLY THE SCALP.

IDENTIFY WHICH OF THESE ARTERIES ARE

BRANCHES OF THE EXTERNAL CAROTID

ARTERY AND WHICH ARE BRANCHES OF THE

INTERNAL CAROTID ARTERY.

Internal carotid artery:

ophthalmic artery→supratrochlear and supraorbital arteries

External carotid artery:

superficial temporal artery

posterior auricular artery

occipital artery

THE SCALP CONTAINS NUMEROUS VESSELS

AND NERVES.

Branches of ophthalmic

artery (a direct branch of

internal carotid artery)

Direct branches of

external carotid artery

IDENTIFY THE DANGER SPACE OF THE SCALP

AND DISCUSS ITS SIGNIFICANCE WITH

RESPECT TO THE SPREAD OF SCALP

INFECTIONS.

Danger space of the scalp: Loose Connective tissue layer

Comprised of the loose connective tissue layer—so named because pus or

blood spreads easily within this layer.

Infections in the loose connective tissue layer can also spread to the cranial

cavity via emissary veins. Because the occipital belly of the occipitofrontalis

muscle attaches firmly to the occipital bone, and the epicranial aponeurosis

attaches firmly to the zygomatic arches, infections or blood in the “danger

space” cannot spread into the neck. However, because the frontal belly of the

occipitofrontalis muscle inserts into skin, infections and blood in the “danger

space” can and do spread to the eyelids and bridge of the nose

DESCRIBE EMISSARY VEINS. DISCUSS THE

SIGNIFICANCE OF EMISSARY VEINS TO THE

SPREAD OF FACE & SCALP INFECTIONS TO THE

CRANIAL CAVITY.

Emissary veins are a connection between the dural venous sinuses and the

veins of the scalp. Emissary veins travel through small foramina in the calvaria.

Infections in the loose connective tissue layer of the scalp can spread through

these valveless veins and reach the cranial cavity.

IDENTIFY THE TWO PRINCIPAL ROUTES

THROUGH WHICH VENOUS BLOOD FROM THE

FACE AND SCALP CAN FLOW TO THE

CAVERNOUS SINUS.

The pterygoid plexus is located on the surfaces of the pterygoid muscles. These structures

are located in the infratemporal fossa. The pterygoid plexus connects to the cavernous

sinus, and this is the route blood would take to reach the cavernous sinuses from the

pterygoid plexus.

Venous blood from the face drains via the facial vein. The pterygoid plexus communicates

with the facial vein via the deep facial vein and ophthalmic vein (connection not shown in

above diagram). As previously discussed, the pterygoid plexus subsequently

communicates with the cavernous sinus.

Venous blood from the anterior scalp reaches the cavernous sinus via branches of the

ophthalmic vein on the scalp. These are presumably named the supratrochlear and

supraorbital veins.

LIST THE STRUCTURES POTENTIALLY AFFECTED

IN CAVERNOUS SINUS THROMBOPHLEBITIS

Abducens nerve (CN VI)—according to Wikipedia, the most commonly affected

Internal carotid artery

Oculomotor nerve (CN III)

Trochlear nerve (CN IV)

Opthalmic branch of the trigeminal nerve (CN V1)

Maxillary branch of the trigeminal nerve (CN V2)

(Pituitary gland)

CAVERNOUS SINUS

IDENTIFY THE BONY ARTICULATIONS OF THE

TEMPOROMANDIBULAR JOINT. LIST THE

MOVEMENTS ALLOWED AT THIS JOINT.

“The temporomandibular joint (TMJ) occurs between the mandibular fossa of

the temporal bone and the condyle of the mandible.

Four movements are allowed at this joint:

Protrusion

Retraction

Elevation

Depression

RELATE THE MOVEMENTS AT THE TMJ TO THE

ARTICULAR DISC INCLUDED WITHIN

The articular disk within the TMJ divides it into two separate synovial capsules

(and thus separate functions).

superior capsule—allows for gliding movements within the mandibular fossa

(protrusion/retraction)

inferior capsule—allows for rotation of the mandibular condyle against the

articular disk (elevation/depression)

The coordination of these two “joints” allow the mouth to open widely.

IDENTIFY THE SENSORY DOMAINS OF THE

FOLLOWING SENSORY BRANCHES OF V3:

AURICULOTEMPORAL, BUCCAL, LINGUAL,

INFERIOR ALVEOLAR, MENTAL

buccal: skin and mucosa of cheek (Maxillary)

inferior alveolar: gingivae and teeth of lower jaw (Maxillary)

auriculotemporal: outer surface of tympanic membrane (Mandibular)

lingual: tongue (Mandibular)

mental: anterior aspects of the chin and lower lip as well as the buccal gingivae

of the mandibular anterior teeth and the premolars

Inferior auricular mandibular

IDENTIFY THE FASCIAL LAYER OF ORIGIN OF

THE PAROTID SHEATH. DISCUSS THE

SIGNIFICANCE OF THE PAROTID SHEATH WITH

RESPECT TO THE PAIN ASSOCIATED WITH

PAROTID INFECTIONS.

Origin of parotid sheath: the investing (superficial) layer of the deep cervical

fascia (head and neck handout)

Role of sheath in pain associated with parotid infections: Infection causes

inflammation and swelling of the parotid gland. Severe pain occurs because the

parotid sheath limits swelling.

IDENTIFY THE STRUCTURES AT RISK OF INJURY

IN A PAROTIDECTOMY AND IN FACIAL

LACERATIONS.

branches of facial nerve along with the parotid duct (class PP)

external carotid artery

LIST THE FOUR CLINICALLY IMPORTANT

GROUPS OF LYMPH NODES OF THE

PERICERVICAL COLLAR AND DESCRIBE, IN

GENERAL TERMS, THE ANATOMICAL LOCATIONS

OF EACH.

Parotid nodes - attached to the superficial surface of the parotid gland and

embedded within it (lowest members are sometimes referred to as “superficial

cervical nodes”)

Submandibular nodes - attached to superficial surface of submandibular gland

and embedded within it

Submental nodes - located inferior to the chin in anterior neck

Mastoid nodes – superior to sternocleidomastoid muscle

IDENTIFY THE STRUCTURES OF THE HEAD AND

NECK INNERVATED BY THE SYMPATHETIC

NERVOUS SYSTEM.

Body wall viscera

Sweat glands

Arrector pili muscles

Smooth muscle in the walls of blood vessels

Dilator pupillae – “muscle” of the iris formed by myoepithelium

Superior tarsal muscle – muscle of the upper eyelid

Salivary glands

IDENTIFY THE PARAVERTEBRAL (CHAIN)

GANGLIA THAT CONTAIN THE POSTGANGLIONIC

SYMPATHETIC NEURONS THAT INNERVATE

THESE STRUCTURES.

The paravertebral (chain) ganglia involved are located in the cervical region

and have fused into three cervical ganglia: superior, middle, and inferior:

Superior cervical ganglion – C1-C4

Middle cervical ganglion – C5-C6

Inferior cervical ganglion – C7-C8 & usually one or more thoracic ganglia

creating the cervicothoracic or “stellate” ganglia

IDENTIFY THE SPINAL CORD SEGMENTS THAT

CONTAIN THE PREGANGLIONIC SYMPATHETIC

NEURONS INVOLVED IN THE INNERVATION OF

HEAD & NECK STRUCTURES.

T1-T4

LIST THE SYMPTOMS OF HORNER’S SYNDROME

AND IDENTIFY ITS ETIOLOGY.

Horner’s syndrome results from the interruption of a cervical sympathetic trunk and is manifested by the absence of sympathetically stimulated functions on the ipsilateral side of the head. This disruption of the sympathetic supply to the head and neck can be a consequence of many pathological conditions and is often a product of compression of the sympathetic chain, especially seen in lung tumors.

Symptoms:

Ptosis – drooping of superior eyelid – due to loss of function of superior tarsal muscle

Miosis – constriction of the pupil – due to unopposed action of constrictor pupillae muscle

Anhidrosis – absence of sweating – due to loss of sympathetic innervation to sweat glands

Vasodilation – redness and increased temperature of the skin

IDENTIFY THE CRANIAL NERVE ASSOCIATED

WITH EACH PHARYNGEAL ARCH. IDENTIFY THE

SKELETAL ELEMENTS (CARTILAGE AND BONE)

DERIVED FROM ARCHES 2-6.

IDENTIFY THE STRUCTURES DERIVED FROM

PHARYNGEAL POUCHES 2-4.

DESCRIBE THE DEVELOPMENTAL BASIS OF A

PYRAMIDAL LOBE OF THE THYROID GLAND AND

ACCESSORY GLANDULAR TISSUE.

Background on development:

Thyroid gland initially appears as a median epithelial thickening in the floor of the

primitive pharynx

It then descends in the neck anterior to the developing hyoid bone and laryngeal

cartilages to its final position anterior to the trachea

During the descent, it receives follicular cells derived from the ultimobranchial body

as well as the superior and inferior parathyroid glands

It also remains connected to the tongue during the descent by a narrow thyroglossal

duct; however, once it gets into its final position the thyroglossal duct should

degenerate

The pyramidal lobe of the thyroid occurs in individuals when the distal portion of the

thyroglossal duct persists instead of degenerating.

DISTINGUISH A THYROGLOSSAL DUCT CYST FROM A

LATERAL CERVICAL CYST.

DESCRIBE THE DEVELOPMENTAL BASIS OF

ECTOPIC PARATHYROID GLANDS

“Because of their extensive migrations during early embryogenesis, parathyroid

glands and components of the thymus gland are often found in abnormal sites.

Ectopic thymic tissue is typically found in the neck; ectopic inferior parathyroid

glands are often found either at the carotid bifurcation or in the superior

mediastinum.”

LIST THE PRIMARY CHARACTERISTICS OF

CATCH-22 SYNDROMES AND RELATE THESE TO

PHARYNGEAL ARCH DEVELOPMENT &

DIFFERENTIATION.

CATCH is the acronym for the symptoms often seen in syndromes involving Chromosome 22 deletions. These symptoms are associated with malformation of Neural Crest Cell derived tissues of the 3rd and 4th pharyngeal arches C: cardiac defects A: abnormal facies T: thymic aplasia causes immune problems C: cleft palate H: hypocalcemia secondary to parathyroid aplasia

Chromosome 22q11 (small arm of 22) deletion syndromes: DiGeorge Syndrome Velocardiofacial Syndrome Conotruncal Anomaly Face Syndrome

IDENTIFY THE SPINAL NERVES THAT FORM THE

CERVICAL PLEXUS AND THEIR CUTANEOUS

BRANCHES. Cervical Plexus is formed by: Ventral Primary Rami of C1 - C4 Spinal Nerves

C1: Lesser Occipital Nerve

C2: Great Auricular Nerve

C3: Transverse Cervical Nerve

C4: Supraclavicular Nerve

“Sometimes considered part of the cervical plexus”: C5: Phrenic Nerve

Innervation:

neck muscles derived from ventral dermomyotomes of cervical somites

skin of anterior and lateral neck

portion of the face and shoulder

DESCRIBE THE ACTION OF THE

STERNOCLEIDOMASTOID MUSCLE (WHEN

ACTING BOTH UNILATERALLY AND

BILATERALLY) AND IDENTIFY ITS INNERVATION.

Sternocleidomastoid:

Origin: sternum + medial ⅓ of clavical; Inserts: mastoid process = Sterno + cl

+ (random “eido”) + mastoid

Action: to see it: http://www.youtube.com/watch?v=4ueRbHZh4js

Unilaterally: tilts the head to the same side while rotating the face in the

opposite direction

Bilaterally: flex cervical spine to bring the chin towards the manubrium

Innervation: Cranial Nerve XI: Spinal Accessory Nerve

DEFINE TORTICOLLIS AND DESCRIBE ITS

TYPICAL PRESENTATION.

Torticollis (“twisted neck”):

Contraction or shortening of the cervical muscles, often congenital

Produces a twisting of the head and slanting of the head

Typical presentation: at birth due to fibrous tissue tumor in the SCM m.

“The most common type of congenital torticollis results from a fibrous tissue

tumor that develops in the sternocleidomastoid muscle before or shortly after

birth. When torticollis occurs prenatally, the abnormal position of the infant’s

head usually necessitates a breech delivery.”

IDENTIFY WHERE IN THE NECK THE SPINAL

ACCESSORY NERVE CAN BE INJURED AND THE

FUNCTIONAL DEFICITS EXPECTED WITH THIS

INJURY.

The Spinal Accessory Nerve crosses through the Posterior (Occipital) Triangle

of the neck

Expected deficits due to CN XI injury:

Paralysis of trapezius

impossible to abduct arm past 90 degrees

can’t shrug shoulders

Also innervates sternocleidomastoid

so.. can’t/weaker flexion of cervical spine or lateral bending of cervical

spine.

IDENTIFY THE VERTEBRAL LEVELS OF THE

FOLLOWING PALPABLE STRUCTURES OF THE

NECK: SUPERIOR BORDER OF THE THYROID

CARTILAGE, CRICOID CARTILAGE.

Superior border of thyroid cartilage – lies opposite the C5 vertebra

Cricoid cartilage – located at level of C6 vertebra

- Marks transition between larynx/trachea (respiratory) and pharynx/esophagus

(digestive)

STELLATE GANGLION BLOCK

Stellate Ganglion Nerve Block – injection of anesthetic into sympathetic tissue

- relieve vasoconstriction after frostbite or microsurgery of hand

- Treat Reynaud phenomenon (reduced blood to toes and fingers because of cold temperatures or emotional stress) and hyperhydrosis (excessive sweating) of the hand

*Note: injection actually made above stellate ganglion, enough anesthetic injected to spread up and down

Needle insertion:

Medially – trachea

Laterally – sternocleidomastoid muscle, common carotid artery

Landmarks – cricoid cartilage (medial) and transverse process of C6 (lateral)

If successful, the following occurs:

Vasodilation – blood vessels of head, neck, upper limb

Horner syndrome (includes these):

Miosis – constriction of pupil

Ptosis – drooping of eyelid

Hemianhydrosis – loss of sweating on one side

CERVICAL PLEXUS BLOCK

Cervical plexus nerve block – needle inserted at vertebral level C3

USE: superficial surgery on neck or thyroid gland, pain management

Landmark: line connecting mastoid process to transverse process of C6

*Note: enough anesthetic injected to spread up and down here too

IDENTIFY THE TRANSVERSE LEVEL OF THE

CAROTID BIFURCATION IN THE NECK AND THE

SURFACE LANDMARK USED TO LOCATE IT.

Bifurcation of the common carotid artery

Common carotid --> internal and external carotid

Occurs in anterior triangle of the neck at level of C4

Surface landmark: thyroid cartilage*

*Note: HYA and Lab instructions say thyroid cartilage at C5 level, so it’s

technically it’s a little below the full bifurcation. See atlas.

DISTINGUISH THE FUNCTIONS OF THE CAROTID

SINUS AND CAROTID BODY.

Carotid sinus – pressure receptor, sensory information carried by CN IX and

CN X

Carotid body – oxygen chemoreceptor, info also carried by CN IX and CN X

IDENTIFY WHERE IN THE NECK THE CAROTID

PULSE CAN BE PALPATED AND DISCUSS

POTENTIAL COMPLICATIONS OF THIS

PROCEDURE.

Carotid pulse – palpated at superior border of thyroid cartilage (C5)

Complication: Pressure on carotid sinus can cause reflex drop in blood

pressure and HR Palpation should be somewhere inferior to superior border of

thyroid cartilage

Most clinicians prefer to use cricoid cartilage (C6).

From lab guide:

When taking the carotid pulse in the neck, the common carotid artery is

compressed against the enlarged anterior tubercle of the C6 vertebra. For this

reason, this tubercle is referred to as the carotid tubercle.

LIST THE THREE LAYERS OF THE DEEP

CERVICAL FASCIA AND THE FOUR CERVICAL

COMPARTMENTS THEY DEFINE. DEFINE THE

"BUCCOPHARYNGEAL FASCIA" AND DESCRIBE

ITS LOCATION.

Prevertebral – surrounding cervical spine and muscles associated with it

Pretracheal – surrounding viscera of neck (larynx/trachea, pharynx/esophagus)

and thyroid gland

Buccopharyngeal fascia – portion of pretracheal fascia located posterior to

wall of pharynx

Investing – outermost layer of deep cervical fascia

FASCIA

IDENTIFY THE LAYERS OF THE DEEP CERVICAL

FASCIA THAT BOUND THE RETROPHARYNGEAL

SPACE. DESCRIBE THE CLINICAL SIGNIFICANCE

OF THIS SPACE.

Retropharyngeal space

deep cervical fascia layers

buccopharyngeal fascia anteriorly

paravertebral fascia posteriorly

Clinical significance

chief avenue for spread of infection from the mouth, the nose, and the throat

to the medastinum of the thorax

LIST THE STRUCTURES ENCLOSED WITHIN THE

CAROTID SHEATH

Carotid artery

Internal jugular vein

Vagus Nerve

DISTINGUISH A CRICOTHYROIDOTOMY FROM A

TRACHEOSTOMY. IDENTIFY THE STRUCTURES AT

POTENTIAL RISK OF INJURY IN TRACHEOSTOMY.

Cricothyroidotomy

incision made in the median cricothyroid ligament

used to quickly establish a temporary airway due to the absence of major

vessels in this location

only used in emergencies because you may accidentally injure the vocal

folds

Tracheostomy

round or square opening is made in the anterior wall of the trachea in order

to insert a tube

structures at potential risk of injury

large blood vessels

thyroid gland

DESCRIBE THE TYPICAL LOCATIONS OF THE

SUPERIOR AND INFERIOR PARATHYROID

GLANDS.

Superior and inferior parathyroid glands

internal to the connective tissue sheath of the thyroid gland, on the posterior

surface of each lobe